/* ── 房贷计算器专题页 ── */

/* Tabs */
.fd-tabs {
    display: flex;
    gap: 0;
    margin-bottom: 1.5rem;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    overflow: hidden;
}

.fd-tab {
    flex: 1;
    padding: 0.75rem 1rem;
    border: none;
    background: #f8f9fb;
    color: #666;
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    font-family: inherit;
}

.fd-tab:not(:last-child) {
    border-right: 1px solid #e0e0e0;
}

.fd-tab:hover {
    background: #eef2ff;
    color: #2563eb;
}

.fd-tab.active {
    background: #2563eb;
    color: white;
}

/* Combo Grid */
.combo-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    margin-bottom: 1rem;
}

.combo-col {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.combo-label {
    font-size: 0.9rem;
    font-weight: 600;
    color: #333;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #2563eb;
}

.combo-col:last-child .combo-label {
    border-bottom-color: #059669;
}

/* Formula Cards */
.formula-cards {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.formula-card {
    background: white;
    border: 1px solid #e8eaf0;
    border-radius: 10px;
    padding: 1.5rem;
}

.formula-title {
    font-size: 1rem;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 0.8rem;
}

.formula-box {
    background: #f8f9fb;
    border: 1px solid #e8eaf0;
    border-radius: 6px;
    padding: 0.8rem 1rem;
    font-family: 'Fira Code', monospace;
    font-size: 0.85rem;
    color: #2563eb;
    margin-bottom: 0.8rem;
    line-height: 1.5;
}

.formula-desc {
    font-size: 0.85rem;
    color: #666;
    line-height: 1.7;
}

/* Mobile */
@media (max-width: 640px) {
    .fd-tabs {
        flex-direction: column;
    }
    .fd-tab:not(:last-child) {
        border-right: none;
        border-bottom: 1px solid #e0e0e0;
    }
    .combo-grid {
        grid-template-columns: 1fr;
    }
    .formula-cards {
        grid-template-columns: 1fr;
    }
}